Lyft's COO, a former Tesla exec, is the latest expert to throw cold water on Elon Musk's plan to have a million robo-taxis on the road by 2020

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Lyft CEO Logan Green (R) and President John Zimmer (C) and COO Jon McNeill (L) laugh before the Nasdaq opening bell celebrating the company's initial public offering (IPO) on March 29, 2019 in Los Angeles, California. The ride hailing app company's shares were initially priced at $72.

• Lyft's COO, a former Tesla executive, is the latest expert to throw cold water on Elon Musk's plan to have a million robo-taxis on the road by next year.
• "I just don't know if that's possible to do," John McNeill told Business Insider in an interview.
• While Lyft is also researching autonomy, McNeill said the company is counting on having human drivers for plenty of years to come.

Plenty of people are skeptical of Elon Musk's vision of one million self-driving Tesla robo-taxis on the streets by next year, even one of his former executives.

John McNeill, Lyft's chief operating officer and former president of global sales and service, didn't go so far as to compare Musk to the great showman PT Barnum, but he did express plenty of doubt for the billionaire's plan.

"I just don't know if that's possible to do," McNeill said in an interview with Business Insider. "What we spend our time thinking about is we've got a future that is driver-based."

Lyft, like Tesla and its major competitor Uber, is investing in self-driving cars too. The company's autonomous shuttles have facilitated more than 35,000 rides in Las Vegas as part of Lyft's partnership with Aptiv, it said in IPO filings earlier this year. However, a wider roll out of that could be years away, and until then, the company is focused on its human drivers.

"What our research shows is that even with autonomy happening over the next few years - or starting to be deployed over the next few years - we'll need more drivers in five years than we have today," McNeill said. "And we'll need more drivers in 10 years than we need in five years. So we're in the long-term driver business."

Lyft says it's barely scraped the surface of its potential market, which includes not just the hundreds of billions of car trips Americans take every year, but also on bikes, scooters and public transit. Shifting all of those to autonomous vehicles won't happen overnight, McNeill said.

"If you add up the overall revenues of Uber and Lyft, let's say we're $30-$35 billion dollars into that one trillion-dollar opportunity," he said. "So over the next five to ten years that $30-$35 billion, or 1% of miles traveled today, grows into that trillion-dollar opportunity. And it grows faster actually, we believe, than the penetration of autonomy."

"If autonomy is serving 5% of rides, you still need 95% of ride service by drivers," McNeill said.

More Lyft news:

• Uber spent $3.3 billion on acquisitions in 2018 and 2019 - 10-times more than Lyft
• Major Wall Street analysts are all bulled up on Lyft, but investors don't seem to care
• Lyft might eventually make money - but it could take 7 years to get there, analyst says

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